Screencast¶
As many questions were raised, we gather here some tips on how-to make beautifull screencast of your simulation.
As mentioned in Ubuntu’s wiki, you can use may way to recorde your desktop, from VLC to ffmpeg, we will present recordmydesktop, a command line tool for which exists as well an interface (gtk-recordmydesktop).
Install using:
sudo apt-get install recordmydesktop
Here is an usefull alias to select a window to record:
alias scast='recordmydesktop --v_bitrate 5000000 --full-shots --fps 10 --no-sound --windowid $(xwininfo | grep "Window id:" | sed -e "s/xwininfo\:\ Window id:\ // ;s/\ .*//")'
The most efficient way to capture is to use low compression, so then you must know how to re-encode your video before sending it.
Official recommendation from YouTube and Vimeo (as of January 2015) are: MP4 + H.264 + AAC-LC.
You can use to following command to re-encode properly:
avconv -i out.ogv -vcodec libx264 -s hd720 -b 5000k -an out.mp4
Or, if you use sound:
avconv -i out.ogv -vcodec libx264 -acodec libfaac -s hd720 -b 5000k -ab 320k out.mp4